New-SSHShellStream: how to figure out when a command has finished executing?

$stream = New-SSHShellStream -SSHSession $ssh
$stream.writeline("someLongRunningCommand")
$stream.read()

I have a simple script that calls a long running script such as ansible playbook that takes a long time to run and outputs different tasks until it's done. How can I tell when the command has finished running? I see the $stream contains properties CanRead, DataAvailable, and CanWrite. CanRead and CanWrite is always True throughout the script running. DataAvailable changes from false to true as data is available to read so then I can call $stream.read() to get the data. So I want to write a loop that can output any data available as the script is running and sleep 1 second between checking for DataAvailable before outputting the data. But I don't know when to break the loop since I don't know when the script has finished executing. I could check the data for the ending line of the script, but if an error occurs in the script and never outputs the expected last line then I'll be stuck in a loop. Any ideas?

Start with the New-SSHShellStream entry point and the stream properties named in the report: CanRead, DataAvailable, and CanWrite. Investigate how command completion or remote-session errors are exposed for long-running commands, then define a reliable completion signal and verify it with a long-running command that succeeds and one that fails.